diff options
Diffstat (limited to 'crypto')
-rw-r--r-- | crypto/asymmetric_keys/Kconfig | 21 | ||||
-rw-r--r-- | crypto/asymmetric_keys/Makefile | 12 | ||||
-rw-r--r-- | crypto/asymmetric_keys/asym_tpm.c | 957 | ||||
-rw-r--r-- | crypto/asymmetric_keys/tpm.asn1 | 5 | ||||
-rw-r--r-- | crypto/asymmetric_keys/tpm_parser.c | 102 |
5 files changed, 0 insertions, 1097 deletions
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 1f1f004dc757..460bc5d0a828 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -22,18 +22,6 @@ config ASYMMETRIC_PUBLIC_KEY_SUBTYPE appropriate hash algorithms (such as SHA-1) must be available. ENOPKG will be reported if the requisite algorithm is unavailable. -config ASYMMETRIC_TPM_KEY_SUBTYPE - tristate "Asymmetric TPM backed private key subtype" - depends on TCG_TPM - depends on TRUSTED_KEYS - select CRYPTO_HMAC - select CRYPTO_SHA1 - select CRYPTO_HASH_INFO - help - This option provides support for TPM backed private key type handling. - Operations such as sign, verify, encrypt, decrypt are performed by - the TPM after the private key is loaded. - config X509_CERTIFICATE_PARSER tristate "X.509 certificate parser" depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE @@ -54,15 +42,6 @@ config PKCS8_PRIVATE_KEY_PARSER private key data and provides the ability to instantiate a crypto key from that data. -config TPM_KEY_PARSER - tristate "TPM private key parser" - depends on ASYMMETRIC_TPM_KEY_SUBTYPE - select ASN1 - help - This option provides support for parsing TPM format blobs for - private key data and provides the ability to instantiate a crypto key - from that data. - config PKCS7_MESSAGE_PARSER tristate "PKCS#7 message parser" depends on X509_CERTIFICATE_PARSER diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index 28b91adba2ae..c38424f55b08 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -11,7 +11,6 @@ asymmetric_keys-y := \ signature.o obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o -obj-$(CONFIG_ASYMMETRIC_TPM_KEY_SUBTYPE) += asym_tpm.o # # X.509 Certificate handling @@ -75,14 +74,3 @@ verify_signed_pefile-y := \ $(obj)/mscode_parser.o: $(obj)/mscode.asn1.h $(obj)/mscode.asn1.h $(obj)/mscode.asn1.o: $(obj)/mscode.asn1.c $(obj)/mscode.asn1.h - -# -# TPM private key parsing -# -obj-$(CONFIG_TPM_KEY_PARSER) += tpm_key_parser.o -tpm_key_parser-y := \ - tpm.asn1.o \ - tpm_parser.o - -$(obj)/tpm_parser.o: $(obj)/tpm.asn1.h -$(obj)/tpm.asn1.o: $(obj)/tpm.asn1.c $(obj)/tpm.asn1.h diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c deleted file mode 100644 index 0959613560b9..000000000000 --- a/crypto/asymmetric_keys/asym_tpm.c +++ /dev/null @@ -1,957 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#define pr_fmt(fmt) "ASYM-TPM: "fmt -#include <linux/slab.h> -#include <linux/module.h> -#include <linux/export.h> -#include <linux/kernel.h> -#include <linux/seq_file.h> -#include <linux/scatterlist.h> -#include <linux/tpm.h> -#include <linux/tpm_command.h> -#include <crypto/akcipher.h> -#include <crypto/hash.h> -#include <crypto/sha1.h> -#include <asm/unaligned.h> -#include <keys/asymmetric-subtype.h> -#include <keys/trusted_tpm.h> -#include <crypto/asym_tpm_subtype.h> -#include <crypto/public_key.h> - -#define TPM_ORD_FLUSHSPECIFIC 186 -#define TPM_ORD_LOADKEY2 65 -#define TPM_ORD_UNBIND 30 -#define TPM_ORD_SIGN 60 - -#define TPM_RT_KEY 0x00000001 - -/* - * Load a TPM key from the blob provided by userspace - */ -static int tpm_loadkey2(struct tpm_buf *tb, - uint32_t keyhandle, unsigned char *keyauth, - const unsigned char *keyblob, int keybloblen, - uint32_t *newhandle) -{ - unsigned char nonceodd[TPM_NONCE_SIZE]; - unsigned char enonce[TPM_NONCE_SIZE]; - unsigned char authdata[SHA1_DIGEST_SIZE]; - uint32_t authhandle = 0; - unsigned char cont = 0; - uint32_t ordinal; - int ret; - - ordinal = htonl(TPM_ORD_LOADKEY2); - - /* session for loading the key */ - ret = oiap(tb, &authhandle, enonce); - if (ret < 0) { - pr_info("oiap failed (%d)\n", ret); - return ret; - } - - /* generate odd nonce */ - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); - if (ret < 0) { - pr_info("tpm_get_random failed (%d)\n", ret); - return ret; - } - - /* calculate authorization HMAC value */ - ret = TSS_authhmac(authdata, keyauth, SHA1_DIGEST_SIZE, enonce, - nonceodd, cont, sizeof(uint32_t), &ordinal, - keybloblen, keyblob, 0, 0); - if (ret < 0) - return ret; - - /* build the request buffer */ - tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_LOADKEY2); - tpm_buf_append_u32(tb, keyhandle); - tpm_buf_append(tb, keyblob, keybloblen); - tpm_buf_append_u32(tb, authhandle); - tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE); - tpm_buf_append_u8(tb, cont); - tpm_buf_append(tb, authdata, SHA1_DIGEST_SIZE); - - ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); - if (ret < 0) { - pr_info("authhmac failed (%d)\n", ret); - return ret; - } - - ret = TSS_checkhmac1(tb->data, ordinal, nonceodd, keyauth, - SHA1_DIGEST_SIZE, 0, 0); - if (ret < 0) { - pr_info("TSS_checkhmac1 failed (%d)\n", ret); - return ret; - } - - *newhandle = LOAD32(tb->data, TPM_DATA_OFFSET); - return 0; -} - -/* - * Execute the FlushSpecific TPM command - */ -static int tpm_flushspecific(struct tpm_buf *tb, uint32_t handle) -{ - tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_FLUSHSPECIFIC); - tpm_buf_append_u32(tb, handle); - tpm_buf_append_u32(tb, TPM_RT_KEY); - - return trusted_tpm_send(tb->data, MAX_BUF_SIZE); -} - -/* - * Decrypt a blob provided by userspace using a specific key handle. - * The handle is a well known handle or previously loaded by e.g. LoadKey2 - */ -static int tpm_unbind(struct tpm_buf *tb, - uint32_t keyhandle, unsigned char *keyauth, - const unsigned char *blob, uint32_t bloblen, - void *out, uint32_t outlen) -{ - unsigned char nonceodd[TPM_NONCE_SIZE]; - unsigned char enonce[TPM_NONCE_SIZE]; - unsigned char authdata[SHA1_DIGEST_SIZE]; - uint32_t authhandle = 0; - unsigned char cont = 0; - uint32_t ordinal; - uint32_t datalen; - int ret; - - ordinal = htonl(TPM_ORD_UNBIND); - datalen = htonl(bloblen); - - /* session for loading the key */ - ret = oiap(tb, &authhandle, enonce); - if (ret < 0) { - pr_info("oiap failed (%d)\n", ret); - return ret; - } - - /* generate odd nonce */ - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); - if (ret < 0) { - pr_info("tpm_get_random failed (%d)\n", ret); - return ret; - } - - /* calculate authorization HMAC value */ - ret = TSS_authhmac(authdata, keyauth, SHA1_DIGEST_SIZE, enonce, - nonceodd, cont, sizeof(uint32_t), &ordinal, - sizeof(uint32_t), &datalen, - bloblen, blob, 0, 0); - if (ret < 0) - return ret; - - /* build the request buffer */ - tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_UNBIND); - tpm_buf_append_u32(tb, keyhandle); - tpm_buf_append_u32(tb, bloblen); - tpm_buf_append(tb, blob, bloblen); - tpm_buf_append_u32(tb, authhandle); - tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE); - tpm_buf_append_u8(tb, cont); - tpm_buf_append(tb, authdata, SHA1_DIGEST_SIZE); - - ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); - if (ret < 0) { - pr_info("authhmac failed (%d)\n", ret); - return ret; - } - - datalen = LOAD32(tb->data, TPM_DATA_OFFSET); - - ret = TSS_checkhmac1(tb->data, ordinal, nonceodd, - keyauth, SHA1_DIGEST_SIZE, - sizeof(uint32_t), TPM_DATA_OFFSET, - datalen, TPM_DATA_OFFSET + sizeof(uint32_t), - 0, 0); - if (ret < 0) { - pr_info("TSS_checkhmac1 failed (%d)\n", ret); - return ret; - } - - memcpy(out, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), - min(outlen, datalen)); - - return datalen; -} - -/* - * Sign a blob provided by userspace (that has had the hash function applied) - * using a specific key handle. The handle is assumed to have been previously - * loaded by e.g. LoadKey2. - * - * Note that the key signature scheme of the used key should be set to - * TPM_SS_RSASSAPKCS1v15_DER. This allows the hashed input to be of any size - * up to key_length_in_bytes - 11 and not be limited to size 20 like the - * TPM_SS_RSASSAPKCS1v15_SHA1 signature scheme. - */ -static int tpm_sign(struct tpm_buf *tb, - uint32_t keyhandle, unsigned char *keyauth, - const unsigned char *blob, uint32_t bloblen, - void *out, uint32_t outlen) -{ - unsigned char nonceodd[TPM_NONCE_SIZE]; - unsigned char enonce[TPM_NONCE_SIZE]; - unsigned char authdata[SHA1_DIGEST_SIZE]; - uint32_t authhandle = 0; - unsigned char cont = 0; - uint32_t ordinal; - uint32_t datalen; - int ret; - - ordinal = htonl(TPM_ORD_SIGN); - datalen = htonl(bloblen); - - /* session for loading the key */ - ret = oiap(tb, &authhandle, enonce); - if (ret < 0) { - pr_info("oiap failed (%d)\n", ret); - return ret; - } - - /* generate odd nonce */ - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); - if (ret < 0) { - pr_info("tpm_get_random failed (%d)\n", ret); - return ret; - } - - /* calculate authorization HMAC value */ - ret = TSS_authhmac(authdata, keyauth, SHA1_DIGEST_SIZE, enonce, - nonceodd, cont, sizeof(uint32_t), &ordinal, - sizeof(uint32_t), &datalen, - bloblen, blob, 0, 0); - if (ret < 0) - return ret; - - /* build the request buffer */ - tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_SIGN); - tpm_buf_append_u32(tb, keyhandle); - tpm_buf_append_u32(tb, bloblen); - tpm_buf_append(tb, blob, bloblen); - tpm_buf_append_u32(tb, authhandle); - tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE); - tpm_buf_append_u8(tb, cont); - tpm_buf_append(tb, authdata, SHA1_DIGEST_SIZE); - - ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); - if (ret < 0) { - pr_info("authhmac failed (%d)\n", ret); - return ret; - } - - datalen = LOAD32(tb->data, TPM_DATA_OFFSET); - - ret = TSS_checkhmac1(tb->data, ordinal, nonceodd, - keyauth, SHA1_DIGEST_SIZE, - sizeof(uint32_t), TPM_DATA_OFFSET, - datalen, TPM_DATA_OFFSET + sizeof(uint32_t), - 0, 0); - if (ret < 0) { - pr_info("TSS_checkhmac1 failed (%d)\n", ret); - return ret; - } - - memcpy(out, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), - min(datalen, outlen)); - - return datalen; -} - -/* Room to fit two u32 zeros for algo id and parameters length. */ -#define SETKEY_PARAMS_SIZE (sizeof(u32) * 2) - -/* - * Maximum buffer size for the BER/DER encoded public key. The public key - * is of the form SEQUENCE { INTEGER n, INTEGER e } where n is a maximum 2048 - * bit key and e is usually 65537 - * The encoding overhead is: - * - max 4 bytes for SEQUENCE - * - max 4 bytes for INTEGER n type/length - * - 257 bytes of n - * - max 2 bytes for INTEGER e type/length - * - 3 bytes of e - * - 4+4 of zeros for set_pub_key parameters (SETKEY_PARAMS_SIZE) - */ -#define PUB_KEY_BUF_SIZE (4 + 4 + 257 + 2 + 3 + SETKEY_PARAMS_SIZE) - -/* - * Provide a part of a description of the key for /proc/keys. - */ -static void asym_tpm_describe(const struct key *asymmetric_key, - struct seq_file *m) -{ - struct tpm_key *tk = asymmetric_key->payload.data[asym_crypto]; - - if (!tk) - return; - - seq_printf(m, "TPM1.2/Blob"); -} - -static void asym_tpm_destroy(void *payload0, void *payload3) -{ - struct tpm_key *tk = payload0; - - if (!tk) - return; - - kfree(tk->blob); - tk->blob_len = 0; - - kfree(tk); -} - -/* How many bytes will it take to encode the length */ -static inline uint32_t definite_length(uint32_t len) -{ - if (len <= 127) - return 1; - if (len <= 255) - return 2; - return 3; -} - -static inline uint8_t *encode_tag_length(uint8_t *buf, uint8_t tag, - uint32_t len) -{ - *buf++ = tag; - - if (len <= 127) { - buf[0] = len; - return buf + 1; - } - - if (len <= 255) { - buf[0] = 0x81; - buf[1] = len; - return buf + 2; - } - - buf[0] = 0x82; - put_unaligned_be16(len, buf + 1); - return buf + 3; -} - -static uint32_t derive_pub_key(const void *pub_key, uint32_t len, uint8_t *buf) -{ - uint8_t *cur = buf; - uint32_t n_len = definite_length(len) + 1 + len + 1; - uint32_t e_len = definite_length(3) + 1 + 3; - uint8_t e[3] = { 0x01, 0x00, 0x01 }; - - /* SEQUENCE */ - cur = encode_tag_length(cur, 0x30, n_len + e_len); - /* INTEGER n */ - cur = encode_tag_length(cur, 0x02, len + 1); - cur[0] = 0x00; - memcpy(cur + 1, pub_key, len); - cur += len + 1; - cur = encode_tag_length(cur, 0x02, sizeof(e)); - memcpy(cur, e, sizeof(e)); - cur += sizeof(e); - /* Zero parameters to satisfy set_pub_key ABI. */ - memzero_explicit(cur, SETKEY_PARAMS_SIZE); - - return cur - buf; -} - -/* - * Determine the crypto algorithm name. - */ -static int determine_akcipher(const char *encoding, const char *hash_algo, - char alg_name[CRYPTO_MAX_ALG_NAME]) -{ - if (strcmp(encoding, "pkcs1") == 0) { - if (!hash_algo) { - strcpy(alg_name, "pkcs1pad(rsa)"); - return 0; - } - - if (snprintf(alg_name, CRYPTO_MAX_ALG_NAME, "pkcs1pad(rsa,%s)", - hash_algo) >= CRYPTO_MAX_ALG_NAME) - return -EINVAL; - - return 0; - } - - if (strcmp(encoding, "raw") == 0) { - strcpy(alg_name, "rsa"); - return 0; - } - - return -ENOPKG; -} - -/* - * Query information about a key. - */ -static int tpm_key_query(const struct kernel_pkey_params *params, - struct kernel_pkey_query *info) -{ - struct tpm_key *tk = params->key->payload.data[asym_crypto]; - int ret; - char alg_name[CRYPTO_MAX_ALG_NAME]; - struct crypto_akcipher *tfm; - uint8_t der_pub_key[PUB_KEY_BUF_SIZE]; - uint32_t der_pub_key_len; - int len; - - /* TPM only works on private keys, public keys still done in software */ - ret = determine_akcipher(params->encoding, params->hash_algo, alg_name); - if (ret < 0) - return ret; - - tfm = crypto_alloc_akcipher(alg_name, 0, 0); - if (IS_ERR(tfm)) - return PTR_ERR(tfm); - - der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len, - der_pub_key); - - ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len); - if (ret < 0) - goto error_free_tfm; - - len = crypto_akcipher_maxsize(tfm); - - info->key_size = tk->key_len; - info->max_data_size = tk->key_len / 8; - info->max_sig_size = len; - info->max_enc_size = len; - info->max_dec_size = tk->key_len / 8; - - info->supported_ops = KEYCTL_SUPPORTS_ENCRYPT | - KEYCTL_SUPPORTS_DECRYPT | - KEYCTL_SUPPORTS_VERIFY | - KEYCTL_SUPPORTS_SIGN; - - ret = 0; -error_free_tfm: - crypto_free_akcipher(tfm); - pr_devel("<==%s() = %d\n", __func__, ret); - return ret; -} - -/* - * Encryption operation is performed with the public key. Hence it is done - * in software - */ -static int tpm_key_encrypt(struct tpm_key *tk, - struct kernel_pkey_params *params, - const void *in, void *out) -{ - char alg_name[CRYPTO_MAX_ALG_NAME]; - struct crypto_akcipher *tfm; - struct akcipher_request *req; - struct crypto_wait cwait; - struct scatterlist in_sg, out_sg; - uint8_t der_pub_key[PUB_KEY_BUF_SIZE]; - uint32_t der_pub_key_len; - int ret; - - pr_devel("==>%s()\n", __func__); - - ret = determine_akcipher(params->encoding, params->hash_algo, alg_name); - if (ret < 0) - return ret; - - tfm = crypto_alloc_akcipher(alg_name, 0, 0); - if (IS_ERR(tfm)) - return PTR_ERR(tfm); - - der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len, - der_pub_key); - - ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len); - if (ret < 0) - goto error_free_tfm; - - ret = -ENOMEM; - req = akcipher_request_alloc(tfm, GFP_KERNEL); - if (!req) - goto error_free_tfm; - - sg_init_one(&in_sg, in, params->in_len); - sg_init_one(&out_sg, out, params->out_len); - akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len, - params->out_len); - crypto_init_wait(&cwait); - akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | - CRYPTO_TFM_REQ_MAY_SLEEP, - crypto_req_done, &cwait); - - ret = crypto_akcipher_encrypt(req); - ret = crypto_wait_req(ret, &cwait); - - if (ret == 0) - ret = req->dst_len; - - akcipher_request_free(req); -error_free_tfm: - crypto_free_akcipher(tfm); - pr_devel("<==%s() = %d\n", __func__, ret); - return ret; -} - -/* - * Decryption operation is performed with the private key in the TPM. - */ -static int tpm_key_decrypt(struct tpm_key *tk, - struct kernel_pkey_params *params, - const void *in, void *out) -{ - struct tpm_buf tb; - uint32_t keyhandle; - uint8_t srkauth[SHA1_DIGEST_SIZE]; - uint8_t keyauth[SHA1_DIGEST_SIZE]; - int r; - - pr_devel("==>%s()\n", __func__); - - if (params->hash_algo) - return -ENOPKG; - - if (strcmp(params->encoding, "pkcs1")) - return -ENOPKG; - - r = tpm_buf_init(&tb, 0, 0); - if (r) - return r; - - /* TODO: Handle a non-all zero SRK authorization */ - memset(srkauth, 0, sizeof(srkauth)); - - r = tpm_loadkey2(&tb, SRKHANDLE, srkauth, - tk->blob, tk->blob_len, &keyhandle); - if (r < 0) { - pr_devel("loadkey2 failed (%d)\n", r); - goto error; - } - - /* TODO: Handle a non-all zero key authorization */ - memset(keyauth, 0, sizeof(keyauth)); - - r = tpm_unbind(&tb, keyhandle, keyauth, - in, params->in_len, out, params->out_len); - if (r < 0) - pr_devel("tpm_unbind failed (%d)\n", r); - - if (tpm_flushspecific(&tb, keyhandle) < 0) - pr_devel("flushspecific failed (%d)\n", r); - -error: - tpm_buf_destroy(&tb); - pr_devel("<==%s() = %d\n", __func__, r); - return r; -} - -/* - * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2]. - */ -static const u8 digest_info_md5[] = { - 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, - 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, /* OID */ - 0x05, 0x00, 0x04, 0x10 -}; - -static const u8 digest_info_sha1[] = { - 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, - 0x2b, 0x0e, 0x03, 0x02, 0x1a, - 0x05, 0x00, 0x04, 0x14 -}; - -static const u8 digest_info_rmd160[] = { - 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, - 0x2b, 0x24, 0x03, 0x02, 0x01, - 0x05, 0x00, 0x04, 0x14 -}; - -static const u8 digest_info_sha224[] = { - 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, - 0x05, 0x00, 0x04, 0x1c -}; - -static const u8 digest_info_sha256[] = { - 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, - 0x05, 0x00, 0x04, 0x20 -}; - -static const u8 digest_info_sha384[] = { - 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, - 0x05, 0x00, 0x04, 0x30 -}; - -static const u8 digest_info_sha512[] = { - 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, - 0x05, 0x00, 0x04, 0x40 -}; - -static const struct asn1_template { - const char *name; - const u8 *data; - size_t size; -} asn1_templates[] = { -#define _(X) { #X, digest_info_##X, sizeof(digest_info_##X) } - _(md5), - _(sha1), - _(rmd160), - _(sha256), - _(sha384), - _(sha512), - _(sha224), - { NULL } -#undef _ -}; - -static const struct asn1_template *lookup_asn1(const char *name) -{ - const struct asn1_template *p; - - for (p = asn1_templates; p->name; p++) - if (strcmp(name, p->name) == 0) - return p; - return NULL; -} - -/* - * Sign operation is performed with the private key in the TPM. - */ -static int tpm_key_sign(struct tpm_key *tk, - struct kernel_pkey_params *params, - const void *in, void *out) -{ - struct tpm_buf tb; - uint32_t keyhandle; - uint8_t srkauth[SHA1_DIGEST_SIZE]; - uint8_t keyauth[SHA1_DIGEST_SIZE]; - void *asn1_wrapped = NULL; - uint32_t in_len = params->in_len; - int r; - - pr_devel("==>%s()\n", __func__); - - if (strcmp(params->encoding, "pkcs1")) - return -ENOPKG; - - if (params->hash_algo) { - const struct asn1_template *asn1 = - lookup_asn1(params->hash_algo); - - if (!asn1) - return -ENOPKG; - - /* request enough space for the ASN.1 template + input hash */ - asn1_wrapped = kzalloc(in_len + asn1->size, GFP_KERNEL); - if (!asn1_wrapped) - return -ENOMEM; - - /* Copy ASN.1 template, then the input */ - memcpy(asn1_wrapped, asn1->data, asn1->size); - memcpy(asn1_wrapped + asn1->size, in, in_len); - - in = asn1_wrapped; - in_len += asn1->size; - } - - if (in_len > tk->key_len / 8 - 11) { - r = -EOVERFLOW; - goto error_free_asn1_wrapped; - } - - r = tpm_buf_init(&tb, 0, 0); - if (r) - goto error_free_asn1_wrapped; - - /* TODO: Handle a non-all zero SRK authorization */ - memset(srkauth, 0, sizeof(srkauth)); - - r = tpm_loadkey2(&tb, SRKHANDLE, srkauth, - tk->blob, tk->blob_len, &keyhandle); - if (r < 0) { - pr_devel("loadkey2 failed (%d)\n", r); - goto error_free_tb; - } - - /* TODO: Handle a non-all zero key authorization */ - memset(keyauth, 0, sizeof(keyauth)); - - r = tpm_sign(&tb, keyhandle, keyauth, in, in_len, out, params->out_len); - if (r < 0) - pr_devel("tpm_sign failed (%d)\n", r); - - if (tpm_flushspecific(&tb, keyhandle) < 0) - pr_devel("flushspecific failed (%d)\n", r); - -error_free_tb: - tpm_buf_destroy(&tb); -error_free_asn1_wrapped: - kfree(asn1_wrapped); - pr_devel("<==%s() = %d\n", __func__, r); - return r; -} - -/* - * Do encryption, decryption and signing ops. - */ -static int tpm_key_eds_op(struct kernel_pkey_params *params, - const void *in, void *out) -{ - struct tpm_key *tk = params->key->payload.data[asym_crypto]; - int ret = -EOPNOTSUPP; - - /* Perform the encryption calculation. */ - switch (params->op) { - case kernel_pkey_encrypt: - ret = tpm_key_encrypt(tk, params, in, out); - break; - case kernel_pkey_decrypt: - ret = tpm_key_decrypt(tk, params, in, out); - break; - case kernel_pkey_sign: - ret = tpm_key_sign(tk, params, in, out); - break; - default: - BUG(); - } - - return ret; -} - -/* - * Verify a signature using a public key. - */ -static int tpm_key_verify_signature(const struct key *key, - const struct public_key_signature *sig) -{ - const struct tpm_key *tk = key->payload.data[asym_crypto]; - struct crypto_wait cwait; - struct crypto_akcipher *tfm; - struct akcipher_request *req; - struct scatterlist src_sg[2]; - char alg_name[CRYPTO_MAX_ALG_NAME]; - uint8_t der_pub_key[PUB_KEY_BUF_SIZE]; - uint32_t der_pub_key_len; - int ret; - - pr_devel("==>%s()\n", __func__); - - BUG_ON(!tk); - BUG_ON(!sig); - BUG_ON(!sig->s); - - if (!sig->digest) - return -ENOPKG; - - ret = determine_akcipher(sig->encoding, sig->hash_algo, alg_name); - if (ret < 0) - return ret; - - tfm = crypto_alloc_akcipher(alg_name, 0, 0); - if (IS_ERR(tfm)) - return PTR_ERR(tfm); - - der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len, - der_pub_key); - - ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len); - if (ret < 0) - goto error_free_tfm; - - ret = -ENOMEM; - req = akcipher_request_alloc(tfm, GFP_KERNEL); - if (!req) - goto error_free_tfm; - - sg_init_table(src_sg, 2); - sg_set_buf(&src_sg[0], sig->s, sig->s_size); - sg_set_buf(&src_sg[1], sig->digest, sig->digest_size); - akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size, - sig->digest_size); - crypto_init_wait(&cwait); - akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | - CRYPTO_TFM_REQ_MAY_SLEEP, - crypto_req_done, &cwait); - ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait); - - akcipher_request_free(req); -error_free_tfm: - crypto_free_akcipher(tfm); - pr_devel("<==%s() = %d\n", __func__, ret); - if (WARN_ON_ONCE(ret > 0)) - ret = -EINVAL; - return ret; -} - -/* - * Parse enough information out of TPM_KEY structure: - * TPM_STRUCT_VER -> 4 bytes - * TPM_KEY_USAGE -> 2 bytes - * TPM_KEY_FLAGS -> 4 bytes - * TPM_AUTH_DATA_USAGE -> 1 byte - * TPM_KEY_PARMS -> variable - * UINT32 PCRInfoSize -> 4 bytes - * BYTE* -> PCRInfoSize bytes - * TPM_STORE_PUBKEY - * UINT32 encDataSize; - * BYTE* -> encDataSize; - * - * TPM_KEY_PARMS: - * TPM_ALGORITHM_ID -> 4 bytes - * TPM_ENC_SCHEME -> 2 bytes - * TPM_SIG_SCHEME -> 2 bytes - * UINT32 parmSize -> 4 bytes - * BYTE* -> variable - */ -static int extract_key_parameters(struct tpm_key *tk) -{ - const void *cur = tk->blob; - uint32_t len = tk->blob_len; - const void *pub_key; - uint32_t sz; - uint32_t key_len; - - if (len < 11) - return -EBADMSG; - - /* Ensure this is a legacy key */ - if (get_unaligned_be16(cur + 4) != 0x0015) - return -EBADMSG; - - /* Skip to TPM_KEY_PARMS */ - cur += 11; - len -= 11; - - if (len < 12) - return -EBADMSG; - - /* Make sure this is an RSA key */ - if (get_unaligned_be32(cur) != 0x00000001) - return -EBADMSG; - - /* Make sure this is TPM_ES_RSAESPKCSv15 encoding scheme */ - if (get_unaligned_be16(cur + 4) != 0x0002) - return -EBADMSG; - - /* Make sure this is TPM_SS_RSASSAPKCS1v15_DER signature scheme */ - if (get_unaligned_be16(cur + 6) != 0x0003) - return -EBADMSG; - - sz = get_unaligned_be32(cur + 8); - if (len < sz + 12) - return -EBADMSG; - - /* Move to TPM_RSA_KEY_PARMS */ - len -= 12; - cur += 12; - - /* Grab the RSA key length */ - key_len = get_unaligned_be32(cur); - - switch (key_len) { - case 512: - case 1024: - case 1536: - case 2048: - break; - default: - return -EINVAL; - } - - /* Move just past TPM_KEY_PARMS */ - cur += sz; - len -= sz; - - if (len < 4) - return -EBADMSG; - - sz = get_unaligned_be32(cur); - if (len < 4 + sz) - return -EBADMSG; - - /* Move to TPM_STORE_PUBKEY */ - cur += 4 + sz; - len -= 4 + sz; - - /* Grab the size of the public key, it should jive with the key size */ - sz = get_unaligned_be32(cur); - if (sz > 256) - return -EINVAL; - - pub_key = cur + 4; - - tk->key_len = key_len; - tk->pub_key = pub_key; - tk->pub_key_len = sz; - - return 0; -} - -/* Given the blob, parse it and load it into the TPM */ -struct tpm_key *tpm_key_create(const void *blob, uint32_t blob_len) -{ - int r; - struct tpm_key *tk; - - r = tpm_is_tpm2(NULL); - if (r < 0) - goto error; - - /* We don't support TPM2 yet */ - if (r > 0) { - r = -ENODEV; - goto error; - } - - r = -ENOMEM; - tk = kzalloc(sizeof(struct tpm_key), GFP_KERNEL); - if (!tk) - goto error; - - tk->blob = kmemdup(blob, blob_len, GFP_KERNEL); - if (!tk->blob) - goto error_memdup; - - tk->blob_len = blob_len; - - r = extract_key_parameters(tk); - if (r < 0) - goto error_extract; - - return tk; - -error_extract: - kfree(tk->blob); - tk->blob_len = 0; -error_memdup: - kfree(tk); -error: - return ERR_PTR(r); -} -EXPORT_SYMBOL_GPL(tpm_key_create); - -/* - * TPM-based asymmetric key subtype - */ -struct asymmetric_key_subtype asym_tpm_subtype = { - .owner = THIS_MODULE, - .name = "asym_tpm", - .name_len = sizeof("asym_tpm") - 1, - .describe = asym_tpm_describe, - .destroy = asym_tpm_destroy, - .query = tpm_key_query, - .eds_op = tpm_key_eds_op, - .verify_signature = tpm_key_verify_signature, -}; -EXPORT_SYMBOL_GPL(asym_tpm_subtype); - -MODULE_DESCRIPTION("TPM based asymmetric key subtype"); -MODULE_AUTHOR("Intel Corporation"); -MODULE_LICENSE("GPL v2"); diff --git a/crypto/asymmetric_keys/tpm.asn1 b/crypto/asymmetric_keys/tpm.asn1 deleted file mode 100644 index d7f194232f30..000000000000 --- a/crypto/asymmetric_keys/tpm.asn1 +++ /dev/null @@ -1,5 +0,0 @@ --- --- Unencryted TPM Blob. For details of the format, see: --- http://david.woodhou.se/draft-woodhouse-cert-best-practice.html#I-D.mavrogiannopoulos-tpmuri --- -PrivateKeyInfo ::= OCTET STRING ({ tpm_note_key }) diff --git a/crypto/asymmetric_keys/tpm_parser.c b/crypto/asymmetric_keys/tpm_parser.c deleted file mode 100644 index 96405d8dcd98..000000000000 --- a/crypto/asymmetric_keys/tpm_parser.c +++ /dev/null @@ -1,102 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#define pr_fmt(fmt) "TPM-PARSER: "fmt -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/export.h> -#include <linux/slab.h> -#include <linux/err.h> -#include <keys/asymmetric-subtype.h> -#include <keys/asymmetric-parser.h> -#include <crypto/asym_tpm_subtype.h> -#include "tpm.asn1.h" - -struct tpm_parse_context { - const void *blob; - u32 blob_len; -}; - -/* - * Note the key data of the ASN.1 blob. - */ -int tpm_note_key(void *context, size_t hdrlen, - unsigned char tag, - const void *value, size_t vlen) -{ - struct tpm_parse_context *ctx = context; - - ctx->blob = value; - ctx->blob_len = vlen; - - return 0; -} - -/* - * Parse a TPM-encrypted private key blob. - */ -static struct tpm_key *tpm_parse(const void *data, size_t datalen) -{ - struct tpm_parse_context ctx; - long ret; - - memset(&ctx, 0, sizeof(ctx)); - - /* Attempt to decode the private key */ - ret = asn1_ber_decoder(&tpm_decoder, &ctx, data, datalen); - if (ret < 0) - goto error; - - return tpm_key_create(ctx.blob, ctx.blob_len); - -error: - return ERR_PTR(ret); -} -/* - * Attempt to parse a data blob for a key as a TPM private key blob. - */ -static int tpm_key_preparse(struct key_preparsed_payload *prep) -{ - struct tpm_key *tk; - - /* - * TPM 1.2 keys are max 2048 bits long, so assume the blob is no - * more than 4x that - */ - if (prep->datalen > 256 * 4) - return -EMSGSIZE; - - tk = tpm_parse(prep->data, prep->datalen); - - if (IS_ERR(tk)) - return PTR_ERR(tk); - - /* We're pinning the module by being linked against it */ - __module_get(asym_tpm_subtype.owner); - prep->payload.data[asym_subtype] = &asym_tpm_subtype; - prep->payload.data[asym_key_ids] = NULL; - prep->payload.data[asym_crypto] = tk; - prep->payload.data[asym_auth] = NULL; - prep->quotalen = 100; - return 0; -} - -static struct asymmetric_key_parser tpm_key_parser = { - .owner = THIS_MODULE, - .name = "tpm_parser", - .parse = tpm_key_preparse, -}; - -static int __init tpm_key_init(void) -{ - return register_asymmetric_key_parser(&tpm_key_parser); -} - -static void __exit tpm_key_exit(void) -{ - unregister_asymmetric_key_parser(&tpm_key_parser); -} - -module_init(tpm_key_init); -module_exit(tpm_key_exit); - -MODULE_DESCRIPTION("TPM private key-blob parser"); -MODULE_LICENSE("GPL v2"); |